Device for pressurizing canisters of liquid adhesives and coatings

ABSTRACT

The present invention is a drum pressurization device for safely and reliably pressurizing a liquid storage barrel with air from an air pump. The drum pressurization device includes a housing having a bottom and sides dimensioned and configured to house the barrel, the housing bottom dimensioned and configured to support the bottom of the barrel and the housing sides dimensioned and configured to snugly retain the barrel sides. The device further includes a top movably mounted to the housing sides and movable between an open position wherein the housing top does not engage the top of the barrel and a locked position wherein the housing top is locked in position and securely engages and holds down the top of the barrel housing. The pressurization device further includes a pressure regulator coupled to the barrel for controlling the pressurization of the barrel by the air pump.

FIELD OF THE INVENTION

The invention relates generally to devices for pressurizing canisters for dispensing to sprayers.

BACKGROUND OF THE INVENTION

Liquid products such as liquid adhesives are commonly applied by means of brushes and rollers. In order to speed up production, pressure sprayers are often used to apply these liquid adhesives. Traditionally, pressure spraying liquid adhesives has been achieved by using a traditional pressure spray gun arrangement which uses a pressure pump in combination with a spray gun. The pressure pump generally includes a pneumatically powered liquid pump with an intake line coupled to a supply of liquid adhesive and a discharge line coupled to the spray gun. This system of pressure spraying is very convenient since it permits the user to simply place the intake line in the liquid container and then simply turn on the pump to commence spraying the product. Unfortunately, this system will not work with many water-based adhesives because the liquid adhesive tends to coagulate in the pump and lines.

Another common method of pressure spraying is to place a quantity of spraying liquid in a pressure vessel and then pressurizing the atmosphere in the vessel. The vessel has a discharge port through which the spraying liquid can pass to a discharge line coupled to the spray gun. This system has met with some success for use with water based liquid adhesives; however, this system has several drawbacks. Firstly, the costs of such a system are significant because it requires the use of a pressure vessel and corresponding pressurizing equipment. Furthermore, pressure vessels of this type generally have relatively small pressure chambers and therefore require frequent filling. Finally, this system requires the user to open the pressure vessel and then fill it periodically with liquid adhesive. This in turn requires the user to move barrels of liquid adhesive into proximity with the pressure sprayer and go through the step of transferring the liquid adhesive from the storage barrels to the pressure sprayer. Therefore, this system of pressure spraying is inconvenient and often difficult to use. An improved method of spraying water based liquid adhesives is therefore required; one which enables the use of the original storage barrel as the dispensing vessel.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a drum pressurization device for safely and reliably pressurizing a liquid storage barrel with air from an air pump. The drum pressurization device includes a housing having a bottom and sides dimensioned and configured to house the barrel, the housing bottom dimensioned and configured to support the bottom of the barrel and the housing sides dimensioned and configured to snugly retain the barrel sides. The device further includes a top movably mounted to the housing sides and movable between an open position wherein the housing top does not engage the top of the barrel and a locked position wherein the housing top is locked in position and securely engages and holds down the top of the barrel housing. The pressurization device further includes a pressure regulator coupled to the barrel for controlling the pressurization of the barrel by the air pump.

The present invention is also directed towards a drum pressurization device including a housing dimensioned and configured to house and support the barrel. The device includes a top movably mounted to the housing and movable between an open position wherein the housing top does not engage the top of the barrel and a locked position wherein the housing top is locked in position and securely engages and holds down the top of the barrel housing. The pressurization device further includes a pressure regulator coupled to the barrel for controlling the pressurization of the barrel by an air pump. The device further includes a safety valve which is operatively coupled to the pressure regulator, the safety valve having a closed state preventing the pressure regulator to pressurize the barrel and an open state permitting the regulator to pressurize the barrel, the safety valve being operatively coupled to the top such that the regulator is in its open state only when the top is in its locked position.

With the foregoing in view, and other advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, the invention is herein described by reference to the accompanying drawings forming a part hereof, which includes a description of the preferred typical embodiment of the principles of the present invention.

DESCRIPTION OF THE DRAWINGS

FIG. 1. is a perspective view of a barrel pressurization device made in accordance with the invention showing a barrel about to be pressurized.

FIG. 2. is a perspective view of the barrel pressurization device shown in FIG. 1 showing the barrel removed.

FIG. 3. is a perspective view of the first safety valve portion of a barrel pressurization device made in accordance with the present invention.

In the drawings like characters of reference indicate corresponding parts in the different figures.

DETAILED DESCRIPTION OF THE INVENTION

Referring firstly to FIG. 1, the present invention comprises a pressure spraying device shown generally as item 10 consisting of a storage barrel 12, secured within housing 14 and coupled to pressure regulator 42 and discharge 18. Storage barrel 12 consist of a standard plastic or metal drum barrel of the type commonly used to store liquids such as water based liquid adhesives. Barrel 12 has top 13, sides 15 and bottom 17. Any standard plastic or metal storage barrels may be used; however, the barrels used in the invention as shown will range in size between 50 and 55 gallons. If larger or smaller barrels are to be used, then the size of housing 14 will have to be changed.

Housing 14 consists of a tubular steel frame having a door 20 pivotally connected to main sides 24 and a top 22 which is removably attached to frame sides 24. Door 20 is made from a plurality of steel tubes and is pivotally movable between a locked closed position as shown if FIG. 1 and an open position as shown in FIG. 2. When door 20 is in its open position, it leaves open door way 11 which is dimensioned to permit barrel 12 to pass in and out of the doorway. Door 20 may be locked in its closed position by locking members 50 and 52, or by any other suitable locking mechanism.

Frame sides 24 are made from a plurality of steel tubes and are dimensioned and configured to snugly retain barrel 12 in an upright position. Top 22 consists of a substantially flat member made up of a plurality of steel tubes and generally takes the forms of a triangular frame having corners 21, 23 and 25. Top 22 is dimensioned and configured such that the triangular frame rests flat on top of top portion 13 of barrel 12 and a peripheral edge formed from corners 21, 23 and 25 extend beyond the top portion of the barrel. Corners 21, 23 and 25 extend sufficiently beyond barrel top 13 to permit the corners to be secured to main frame 24 by elongated threaded tie down bolts 27, 29 and 31, respectively. Corners 21, 23 and 25 have apertures 33, 35 and 37, respectively, which are dimensioned and positioned to receive the tie down bolts. When engaged by tie down nuts 40, tie down bolts 27, 29 and 31 firmly anchor top 22 to housing sides 24 such that top portion 13 of barrel 12 cannot move upward.

Air to pressurize the system is supplied by standard air compressor pump 47 which is connected to air intake 34 by standard air line 49. Air intake 34 is coupled to safety valve 38 by air line 36. First safety valve 38 is in turn coupled to pressure regulator assembly 42 by air line 39. Pressure regulator assembly 42 is in turn operatively coupled to safety valve 48 which is coupled to air line 44 which is coupled to safety valve 46 which is in turn coupled to barrel 12. Air regulator 42 is made up of air valves and pressure gauges which are calibrated to precisely control the air pressure in barrel 12 to within an operating range of o to approximately 8 psi. Safety valve 38 is a spring biased shut off valve which is biased towards a shut off state preventing the flow of air from air compressor 47 to air regulator assembly 42. Safety valve 38 is physically coupled to housing top 22 by arm 54. As better seen in FIG. 3, safety valve 38 has a lever 56 which controls the operation of the valve. Lever 56 is spring biased into its closed position. However, when housing top 22 is locked into its closed position, control arm 58 of arm 54 engages lever 56 and forces the lever downwardly to open the safety valve. In this way, safety valve 38 can only be opened when housing top 22 is fully locked in position, thereby preventing the accidental pressurization of barrel 12.

Referring back to FIG. 1, pressure regulator assembly 42 includes safety pressure blow off valve 48. Safety valve 48 is a pressure blow off valve which is calibrated to vent the pressure in regulator assembly 42 when the pressure in the regulator assembly exceeds 8 psi. Safety valve 48 provides a level of safety against accidentally pressurizing barrel 12 to pressures exceeding 8 psi. Safety valve 46 is also a pressure blow off valve which is calibrated to vent the pressure in barrel 12 when the pressure in the barrel exceeds 11 psi. Safety valve 46 provides an additional layer of safety should safety valve 48 fail.

The operation of the present system will now be discussed. Housing 14 is first opened by opening door 20 and removing top 22. A full barrel 12 is then loaded into the housing. Door 20 is closed and locked by engaging locking members 50 and 52. Top 22 is then loaded onto frame 14 positioned in place over barrel top 13. Pressure valve 46 and discharge 18 (to which a fluid line leading to the spray gun is attached) are then coupled to barrel 12. Top 22 is then locked into its locked position. Air line 49 may then be coupled to intake 34 and the air pump may be activated to commence pressurizing the barrel. As the barrel is pressurized, its natural tendency is to deform and balloon outwardly, but since the barrel is securely held in an upright position in housing 14 and since top 22 is locked in place against top 13 of the barrel, the barrel can be safely pressurized without fear of injury resulting from the failure of the barrel. The precise pressure inside the barrel can be adjusted using pressure regulator assembly 42. In the event of a failure of the pressure regulator assembly, safety valves 48 and 46 prevent the barrel from becoming dangerously over pressurized.

A specific embodiment of the present invention has been disclosed; however, several variations of the disclosed embodiment could be envisioned as within the scope of this invention. It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. 

1. A pressure spraying device for spraying a liquid through a spray gun comprising: a storage barrel for storing the liquid, the storage barrel having a top, a bottom and sides; a retaining housing for securely retaining the storage barrel in an upright position, the retaining housing having a bottom, a top and sides, the bottom, the sides and bottom of the housing being dimensioned and configured to fit snugly around the barrel such that the sides of the barrel are constrained by the sides of the housing and the bottom of the barrel is supported by the bottom of the housing; the top of the housing being movably attached to the sides of the housing and movable between an open position wherein the top of the housing does not engage the top of the barrel and a locked position wherein the top of the housing securely engages and holds down the top of the barrel and the top of the housing is locked in position relative to the sides of the housing; the sides of the housing having a door movable between an open and closed position, the door being dimensioned and configured to permit the barrel to pass through the housing when the door is opened; a pressure regulator for controlling the pressurization of the barrel by an air pump, and a discharge line operatively coupled to the barrel for carrying the liquid from the barrel to the spray gun.
 2. The pressure spraying device of claim 1 further comprising a first safety valve operatively coupled to the pressure regulator, the first safety valve functioning between an open state wherein the pressure regulator can pressurize the barrel and a closed state wherein the pressure regulator cannot pressurize the barrel, the first safety valve being operatively coupled to the housing top and housing sides such that the first safety valve is in its open state only when the housing top is in its locked position.
 3. The pressure spraying device of claim 2 further comprising a second safety valve operatively coupled to the pressure regulator, the second safety valve being a blow out valve which vents when the pressure inside the barrel exceeds a first predetermined pressure.
 4. The pressure spraying device of claim 3 further comprising a third safety valve operatively coupled to the barrel, the third safety valve being a blow out valve which vents when the pressure inside the barrel exceeds a second predetermined pressure, the second predetermined pressure being higher than the first predetermined pressure.
 5. The pressure spraying device of claim 1 wherein the housing top is removably mounted to the housing sides by a plurality of connector elements.
 6. The pressure spraying device of claim 1 wherein the housing top is a rigid substantially flat member dimensioned to lay flat against the barrel top when the top is in its locked position.
 7. The pressure spraying device of claim 6 wherein the housing top has peripheral edges which over extend beyond the barrel top and wherein the housing top is mounted to the sides of the frame by a plurality of elongated mounting members which connect the peripheral edges of the housing top to the housing sides.
 8. The pressure spraying device of claim 7 wherein the elongated mounting members comprise mounting bolts.
 9. The pressure spraying device of claim 8 wherein the first safety valve comprises a spring actuated valve which is normally biased towards the closed state, the first valve having a lever which, when activated, moves the valve into its open state, the first valve being positioned on the housing sides such that when the housing top is moved into its locked position a portion of the housing top bears against the lever with sufficient force to move the valve into its opened position.
 10. A drum pressurization device for pressurizing a liquid storage barrel with air from an air pump, said barrel having a top, a bottom and sides, said drum pressurization device comprising: a housing having a bottom and sides dimensioned and configured to house the barrel, the housing bottom dimensioned and configured to support the bottom of the barrel and the housing sides dimensioned and configured to snugly retain the barrel sides; a top movably mounted to the housing sides and movable between an open position wherein the housing top does not engage the top of the barrel and a locked position wherein the housing top is locked in position and securely engages and holds down the top of the barrel housing; a pressure regulator coupled to the barrel for controlling the pressurization of the barrel by the air pump.
 11. The drum pressurization device of claim 10 further comprising a first safety valve operatively coupled to the regulator, the first safety valve functioning between an open state wherein the pressure regulator can pressurize the barrel and a closed state wherein the pressure regulator cannot pressurize the barrel, the first safety valve being operatively coupled to the housing top such that the first safety valve is in its open state only when the housing top is in its locked position.
 12. The drum pressurization device of claim 11 further comprising a second safety valve operatively coupled to the pressure regulator, the second safety valve being a blow out valve which vents when the pressure inside the barrel exceeds a first predetermined pressure level.
 13. The drum pressurization device of claim 12 further comprising a third safety valve operatively coupled to the barrel, the third safety valve being a blow out valve which vents when the pressure inside the barrel exceeds a second predetermined pressure level, the second predetermined pressure level being higher than the first predetermined pressure level.
 14. The drum pressurization device of claim 10 wherein the housing top is a rigid substantially flat member dimensioned to lay flat against the barrel top when the top is in its locked position.
 15. The drum pressurization device of claim 14 wherein the housing top has peripheral edges which over extend beyond the barrel top and wherein the housing top is mounted to the sides of the frame by a plurality of elongated mounting members which connect the peripheral edges of the housing top to the housing sides.
 16. The drum pressurization device of claim 15 wherein the elongated mounting members comprise elongated threaded bolts and wherein the peripheral edges of the housing top is provided with a plurality of apertures each of which is dimensioned to receive one of the bolts, the apertures being positioned along the peripheral edges of the housing top to align with the bolts, and wherein the housing top is secured in its locked position by a plurality of locking nuts secured to the bolts.
 17. The drum pressurization device of claim 16 wherein the first safety valve comprises a spring actuated valve which is normally biased towards the closed state, the first valve having a lever which, when activated, moves the valve into its open state, the first valve being positioned on the housing sides such that when the housing top is moved into its locked position a portion of the housing top bears against the lever with sufficient force to move the valve into its opened position.
 18. A drum pressurization device for pressurizing a standard sized storage barrel with air from an air pump, said barrel having a top, a bottom and sides, said drum pressurization device comprising: a pressure regulator coupled to the barrel and the air pump for controlling the pressurization of the barrel by the air pump; a housing for supporting the barrel in an upright position as the barrel is pressurized, the housing having a bottom and sides dimensioned and configured to house the barrel, the housing bottom dimensioned and configured to support the bottom of the barrel and the housing sides dimensioned and configured to snugly retain the barrel sides and hold the barrel upright as the barrel is pressurized; a top movably mounted to the housing sides and movable between an open position wherein the housing top does not engage the top of the barrel and a locked position wherein the housing top is locked in position to the housing sides and securely engages and holds down the top of the barrel housing; a first safety valve operatively coupled to the pressure regulator, the first safety valve having an open state wherein the pressure regulator can pressurize the barrel and a closed state wherein the pressure regulator cannot pressurize the barrel, the first safety valve being operatively coupled to the housing top such that the first safety valve is in its open state only when the housing top is in its locked position.
 19. The drum pressurization device of claim 18 wherein the housing top is a rigid substantially flat member dimensioned to lay flat against the barrel top when the top is in its locked position, the housing top having peripheral edges which over extend beyond the barrel top and wherein the housing top is mounted to the sides of the frame by a plurality of elongated mounting members which connect the peripheral edges of the housing top to the housing sides.
 20. The drum pressurization device of claim 19 wherein the first safety valve comprises a spring actuated valve which is normally biased towards the closed state, the first valve having a lever which, when activated, moves the valve into its open state, the first valve being positioned on the housing sides such that when the housing top is moved into its locked position a portion of the housing top bears against the lever with sufficient force to move the valve into its opened position. 